Transcript Proving Angles Congruent LESSON 2-5 Additional Examples Find the value of x. The angles with labeled measures are vertical angles because their sides are opposite.

Proving Angles Congruent
LESSON 2-5
Additional Examples
Find the value of x.
The angles with labeled measures are vertical angles because their
sides are opposite rays. Apply the Vertical Angles Theorem to find x.
4x – 101 = 2x + 3
Vertical Angles Theorem
4x = 2x + 104
Addition Property of Equality
2x = 104
Subtraction Property of Equality
x = 52
Division Property of Equality
Quick Check
HELP
GEOMETRY
Proving Angles Congruent
LESSON 2-5
Additional Examples
Write a paragraph proof using the given, what you
are to prove, and the diagram.
Given: WX = YZ
Prove: WY = XZ
Proof: It is given that WX = YZ. Adding the middle segment, XY, to each
smaller segment gives WX + XY = YZ + XY.
By the Segment Addition Postulate, WX + XY = WY, and XY + YZ = XZ.
Using substitution, you get WY = XZ.
Quick Check
HELP
GEOMETRY